After a productive meeting with the Kenya Medical Research Institute (KEMRI) this morning, it was agreed that water testing will begin as early as this Thursday. For those of you who enjoyed your science classes, I thought I’d share the details and objectives of the testing process. This initial round of testing has two parts.
The first test is to determine the optimal amount of chlorine that should be added to the water. Drinking water is treated at the original water source before it is piped into Kibera and other slums. We know from testing performed by the CDC last year that there is some residual chlorine in the water when it reaches the taps, but the chlorine levels are inconsistent and in some cases low enough that unsafe levels of bacteria were found. One of the core Life Force Kiosks (LFK) services will be to “top up” chlorine levels by adding a few drops of chlorine into our customers’ water containers right after they fill them with water. The question is how much to add. Obviously adding more chlorine increases the safety of the drinking water (to a point). Unfortunately, the more chlorine you add, the more the water will start to taste and smell like a swimming pool. Not surprisingly, this is a huge barrier to adoption of liquid chlorine products in the market that give dosage instructions (3 ml chlorine per 20 liters of water) based on the assumption that there’s no chlorine already in the water.
KEMRI will draw 200 water samples from the community and pour each sample into four smaller containers. One container will remain untreated and the other three will be treated with 1, 2, and 3 ml of chlorine. Then they will measure the E. coli counts for each sub-sample. That will allow us to determine the minimum amount of chlorine needed to reduce E. coli counts down to safe levels (as determined by the World Health Organization). Essentially we’re determining the shape and slope of the red line in the graph on the left. Please note that the graph is purely an example and is not populated with real data.
The second test that KEMRI is conducting is on the efficacy of our water storage cleaning methodology. The second core service that LFK offers is to clean water storage containers with soap and chlorinated water. We want to be sure that our cleaning methodology really reduces bacteria levels like we think it will. To be sure, we will take 100 water storage containers directly from residents’ homes. We’ll empty the containers and refill them with sterilized water that starts with no bacterial contamination. After shaking the container lightly, we’ll measure the E. coli count in the water. We’ll then clean the storage containers and repeat the process. If our methodology is effective, we should see significant levels of E. coli in the samples taken from untreated containers, but safe levels after treatment.
The whole process will take roughly 3-4 weeks to complete, barring unexpected delays. I look forward to sharing the results, especially to the first set of tests. If we are correct that a smaller amount of chlorine is needed in these slum environments, it could have a huge impact on chlorine adoption in slums around the world.